Identifying the composition and sequence of various biomolecules, such as human DNA, with accuracy and specificity is of great interest. Sequencing technology, however, is time consuming and expensive to develop and implement. For example, sequencing the DNA of a single individual for the Human Genome Project required over $3 billion of funding.
It is estimated that each person's DNA varies from one another by approximately 1 base in 1000. Knowledge of such genetic variations among human populations may allow the scientific community to identify genetic trends that are related to various medical predispositions, conditions, or diseases, and may lead to the realization of truly personalized medicine where treatments are customized for a given individual based on that individual's DNA. A reduction in the time and cost of DNA sequencing is needed to develop such knowledge and to tailor medical diagnostics and treatments based on the genetic makeup of individual patients.
Hybridization Assisted Nanopore Sequencing (HANS) is a nanopore-based method for sequencing genomic lengths of DNA and other biomolecules. The method relies on detecting the position of hybridization of probes on specific portions of the biomolecule to be sequenced or characterized.
In this method, two reservoirs of solution are separated by a nanometer-sized hole, or nanopore, that serves as a fluidic constriction of known dimensions. The application of a constant DC voltage between the two reservoirs results in a baseline ionic current that is measured. If an analyte is introduced into a reservoir, it may pass through the fluidic channel and change the observed current, due to a difference in conductivity between the electrolyte solution and analyte. The magnitude of the change in current depends on the volume of electrolyte displaced by the analyte while it is in the fluidic channel. The duration of the current change is related to the amount of time that the analyte takes to pass through the nanopore constriction. The current signals are used in determining the position of the probes on the biomolecule by use of computer algorithms. Aligning the probe positions allows for sequencing the biomolecule. Efficient algorithms are needed for sequencing.